Today I got another chance to go out with team CASIMBO to drill ice-cores. The weather was beautiful with no wind, a few clouds, bright sunshine and a balmy temperature of about 5 degrees F.
When I first saw sea ice near Alert a few years ago, I was very surprised. It wasn’t anything like I had imagined. One might expect sea ice to be like lake ice: smooth and flat. But Arctic Ocean ice is in constant motion, driven by winds and ocean currents. Big chunks of ice break-up, smash into each other and create ice that looks more like a rubble field.
As we drove over the icy rubble on our snowmobile, we searched for a route to our sampling location, about 3 to 4 miles away from Alert (45 minutes by snowmobile). Taking an ice-core is relatively simple. One of the pictures shows Ben using the corer. It is basically a plastic pipe with cutting knives at the end that drills into the ice while keeping the ice-core trapped inside. After 3 feet of ice is cored, the corer is lifted out of the hole and the ice core is packed into containers for further processing in Alert.
The ice above was about six feet thick but generally, thickness varies. There is thin ice that has just formed on open water between ice floes, first year ice, or ice that has formed this winter, several-feet thick and ice that has formed over several years that can be more than 20 feet thick.